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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 45 |
| 5 | 81 |
| 6 | 321 |
| 7 | 449 |
| 8 | 1745 |
| 9 | 2945 |
| 10 | 9153 |
| 11 | 11265 |
| 12 | 60609 |
| 13 | 53249 |
| 14 | 230401 |
| 15 | 410625 |
| 16 | 1259777 |
| 17 | 1114113 |
| 18 | 7263233 |
| 19 | 4980737 |
| 20 | 31337473 |
| 21 | 44630017 |
| 22 | 115367937 |
| 23 | 96468993 |
| 24 | 937283585 |
| 25 | 551550977 |
| 26 | 2399256577 |
| 27 | 4594597889 |
| 28 | 14579646465 |
| 29 | 7784628225 |
| 30 | 89894944769 |
| 31 | 33285996545 |
[1,5,13,45,81,321,449,1745,2945,9153,11265,60609, 53249,230401,410625,1259777,1114113,7263233, 4980737,31337473,44630017,115367937,96468993, 937283585,551550977,2399256577,4594597889, 14579646465,7784628225,89894944769,33285996545] |